Fin assmebly and heat dissipation device using the same

ABSTRACT

A heat dissipation device includes a centrifugal fan and a fin assembly aside the centrifugal fan. The centrifugal fan includes a casing and an impeller received in the casing, the casing defines an air outlet at one side thereof. The fin assembly is located at the air outlet of the centrifugal fan. The fin assembly includes a plurality of fins parallel to and spaced from each other. Each of the fins includes a main body and an extending portion extending form the main body toward the air outlet of the centrifugal fan. Each extending portion includes a side edge facing the air outlet of the centrifugal fan, the side edge is arc shaped and inwardly concaved toward the main body.

BACKGROUND

1. Technical Field

The present disclosure relates to heat dissipation devices, and particularly to a heat dissipation device incorporating a fin assembly.

2. Description of Related Art

Heat dissipation devices are often applied to dissipate heat from heat generating components, such as central procession units (CPUs). Generally, a conventional heat dissipation device includes a centrifugal fan and a fin assembly arranged at an air outlet of the fan.

During operation of the heat dissipation device, the fan generates airflow through the fin assembly to take away the heat of the fin assembly absorbed from the heat generating component. However, a difference of an amount of the airflow at two ends of the air outlet is huge, and thus a utilization efficiency of the airflow is low.

Thus, it is desired to overcome the described limitations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an assembled view of a heat dissipation device, according to an exemplary embodiment of the present disclosure.

FIG. 2 is an exploded, isometric view of the heat dissipation device of FIG. 1.

FIG. 3 is a cross-section view of the heat dissipation device of FIG. 1.

FIG. 4 is an enlarge view of a fin of the heat dissipation device of FIG. 1.

DETAILED DESCRIPTION

FIGS. 1, 2 and 3 show a heat dissipation device 100 in accordance with an exemplary embodiment. The heat dissipation device 100 includes a fan 10, and a fin assembly 20 adjacent to the fan 10.

The fan 10 includes a casing 12, and an impeller 14 received in the casing 12. The impeller 14 includes a hub 142, and a plurality of blades 144 extending radially and outwardly from a periphery of the hub 142. The casing 12 includes a top cover 123, a bottom plate 124, and a sidewall 126 connecting the top cover 123 with the bottom plate 124. The top cover 123, the bottom plate 124 and the sidewall 126 cooperatively define a receiving space (not labeled) receiving the impeller 14.

The top cover 123 defines an air inlet 121 at a center thereof. The impeller 14 is rotatably connected to the top cover 123 with the hub 142 thereof aligned with the air inlet 121 of the top cover 123. The sidewall 126 defines an air outlet 122 between two ends of the sidewall 126, perpendicular to the air inlet 121. The impeller 14 is spaced from the sidewall 126, with an air channel 13 defined between the sidewall 126 and outermost free ends of the impeller 14. In this embodiment, the fan 10 rotates clockwise, as viewed from a top side, a first portion 17 is formed at an upstream end of the air channel 13 and a second portion 18 is formed at a downstream end of the air channel 13, the second portion 18 is wider than the first portion 17. An amount of the airflow generated by the fan 10 decreases from the second portion 18 to the first portion 17. When the fan 10 works, air pressure in the first portion 17 is larger than that in the second portion 18.

The fin assembly 20 is disposed at the air outlet 122 of the fan 10, and includes a plurality of fins 21 stacked together. Each fin 21 is parallel to and spaced from a neighboring fin 21. A channel 210 is defined between each two adjacent fins 21 communicating with the air outlet 122 of the fan 10. Each channel 210 comprises an inlet for airflow entering the fin assembly 20 and an outlet for airflow exhausting the fin assembly 20. Each fin 21 includes a main body 24 and an extending portion 22 extending from a lateral edge of the main body 24 adjacent to the fan 20 towards the air outlet 122. A pair of flanges 25 is bent horizontally from a top and a bottom of the main body 24. Each flange 25 is abutted with a flange 25 of a neighboring fin 21. The flanges 25 cooperatively seal the channels 210 at top and bottom sides of the main bodies 24. Thus, the airflow in each channel 210 flows out along direction A as shown in FIG. 4 to exchange heat with the fins 21 at opposite sides of the channel 210.

In addition, except two outmost fins 21, the main body 24 of each fin 21 defines a through hole 26 adjacent to a lateral side thereof away from the fan 10. The hole 26 intercommunicates the channels 210 at opposite sides of each fin 21. Thus, when the airflow flows along the channels 210 to the holes 26, the airflow from the fan 10 is redistributed via the holes 26, especially, to make the airflow from the first portion 17 flow to other channels 210 between the fins 21 remote form the first portion 17; thereby, the mount of the airflow in the fin assembly 20 is more evenly. In the present embodiment, the holes 26 of the fins 21 are arranged in line and cooperatively form an airflow passage extending along direction B, perpendicular to direction A.

Referring also to FIG. 4, the extending portion 22 extends from a central portion of the lateral edge of the main body 24. In this embodiment, the extending portion 22 and the main body 24 are coplanar. A height of the extending portion 22 is less than that of the corresponding main body 24; therefore, each of the fins 21 forms a pair of notches 223 at a top and a bottom portion of the extending portion 22 to engage with the top cover 123 and the bottom plate 124 of the fan 10. Each extending portion 22 includes a side edge 224 between the notches 223 and facing the air outlet 122 of the fan 10. The side edge 224 is arc shaped and inwardly concaved towards the main body 24. In this embodiment, the side edges 224 are at inlets of the channels 210 and concaved towards the outlets of the channels 210. The extending portions 22 of the fin assembly 20 extend into the casing 12 of the fan 10. In this embodiment, the extending portions 22 are sandwiched between the top cover 123 the bottom plate 124.

Due to each of the fins 21 has an extending portion 22, the area of each of the fins 21 is enlarged, as a result, the heat dissipation efficiency of the heat dissipation device 100 is improved. In addition, the side edge 224 of the extending portion 22 of each fin 21 is arc shaped and inwardly concaved, which can reduce the noise.

It is to be further understood that even though numerous characteristics and advantages have been set forth in the foregoing description of embodiments, together with details of the structures and functions of the embodiments, the disclosure is illustrative only; and that changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

What is claimed is:
 1. A fin assembly comprising a plurality of fins defining a plurality of channels therebetween, each channel comprising an inlet for airflow entering the fin assembly and an outlet for airflow exhausting the fin assembly, each fin comprising: a main body; and an extending portion extending from the main body, the extending portion comprising a side edge at the inlet of the channel, the side edge being arc shaped and concaved inwardly towards the outlet.
 2. The fin assembly of claim 1, wherein a pair of flanges bends horizontally from a top and a bottom of the main body, each flange being abutted with a flange of a neighboring fin, a first airflow passage being formed between every two adjacent fins.
 3. The fin assembly of claim 1, wherein the fins comprises two first fins and a plurality of second fins arranged between the two first fins, each of the second fins defining a through hole, the through holes cooperatively defining a second airflow passage.
 4. A heat dissipation device, comprising: a centrifugal fan comprising a casing and an impeller received in the casing, the casing defining an air outlet at one side thereof; and a fin assembly located at the air outlet of the centrifugal fan, the fin assembly comprising a plurality of fins parallel to and spaced from each other, each of the fins comprising a main body and an extending portion extending form the main body toward the air outlet of the centrifugal fan, each extending portion comprising a side edge facing the air outlet of the centrifugal fan, the side edge being arc shaped and inwardly concaved toward the main body.
 5. The heat dissipation device of claim 4, wherein each fin defines a pair of notches at a top and a bottom portion of the extending portion to engage with the centrifugal fan.
 6. The heat dissipation device of claim 5, wherein the casing comprises a top cover, a bottom plate, and a sidewall connecting the top cover with the bottom plate, the top cover, the bottom plate and the sidewall cooperatively defining a receiving space for receiving the impeller, the notches of the fin engaging with the top cover and the bottom plate of the centrifugal fan.
 7. The heat dissipation device of claim 4, wherein a pair of flanges bend horizontally from a top and a bottom of the main body, each flange being abutted with a flange of a neighboring fin, a first airflow passage being formed between every two adjacent fins.
 8. The heat dissipation device of claim 7, wherein the fins further define a second airflow passage perpendicular to the first airflow passage.
 9. The heat dissipation device of claim 8, wherein the fin assembly comprises two first fins and a plurality of second fins arranged between the two first fins, each of the second fins defining a through hole, the through holes defining the second airflow passage.
 10. The heat dissipation device of claim 9, wherein the through hole is arranged away from the centrifugal fan.
 11. The heat dissipation device of claim 6, wherein the extending portions of the fins extend into the casing of the centrifugal fan.
 12. The heat dissipation device of claim 11, wherein the extending portions of the fins are sandwiched between the top cover and the bottom plate.
 13. A heat dissipation device, comprising: a centrifugal fan comprising a casing and an impeller received in the casing, the casing defining an air outlet at one side thereof; and a fin assembly located adjacent to the air outlet of the centrifugal fan, the fin assembly comprising a plurality of fins parallel to and spaced from each other, each of the fins comprising a main body and an extending portion extending form the main body toward the air outlet of the centrifugal fan, each extending portion having a height less than that of the main body.
 14. The heat dissipation device of claim 13, wherein the extending portion and the main body of each of the fins are coplanar with each other.
 15. The heat dissipation device of claim 13, wherein the extending portions of the fins extend into the casing of the centrifugal fan.
 16. The heat dissipation device of claim 14, wherein the extending portion of each of the fins comprises a side edge facing the air outlet of the centrifugal fan, the side edge being arc shaped.
 17. The heat dissipation device of claim 13, wherein the fins comprise two first fins and a plurality of second fins arranged between the two first fins, each of the second fins defining a through hole adjacent to a lateral side thereof away from the centrifugal fan.
 18. he heat dissipation of claim 17, wherein the holes of the fins are arranged in line and cooperatively define an airflow passage extending along a direction perpendicular to a channel defined between each two adjacent fins. 